A neoclassical-realist analysis of Japan’s stance on cross-strait relations [version 1; peer review: awaiting peer review]

Since 1972, Tokyo has maintained official diplomatic relations with Beijing, while stressing the importance of peace and stability across the Taiwan Strait. Based on governmental documents and decision-makers’ political declarations, this article examines Japan’s approach towards cross-strait relations since the 1990s. It applies the perspective of neoclassical realism by analyzing both the international determinants (independent variables) and the domestic factors (intervening variables) behind Tokyo’s approach to ‘One China’ policy. The article tries to answer the question why successive Japanese governments reacted differently to cross-strait frictions and rapprochement. It is argued that the level of Tokyo’s involvement in the Taiwan problem was dependent both on international and domestic factors. Growing concerns about China’s military buildup, coupled with a gradual demise of pro-Beijing faction in the Liberal Democratic Party, pushed Japan towards containing the People’s Republic of China (PRC) while ameliorating relations with Taipei. As Sino-Japanese relations deteriorated, Tokyo became less inclined to lecture Taiwan against provoking Beijing and more willing to support Taipei’s international initiatives. At the same time, Japan started perceiving cross-strait rapprochement not only as a factor stabilizing the regional security system, but also as a potential threat to national security.


Introduction
By officially recognizing the Republic of China (ROC) until 1972 and the People's Republic of China (PRC) since then, Japan has adhered to 'One China' policy. 1 The aim of this article is to examine the evolution of Tokyo's stance on cross-strait relations in the post-Cold War era. The main hypothesis is that while Japan's crucial interest regarding the Taiwan problem lay in stabilizing security situation in the region, the methods to achieve this aim evolved together with the change of international situation and its perception by Japanese decision-makers. As such, depending on domestic factors and the state of cross-strait relations, Tokyo was concerned either with Taipei's rapprochement with Beijing or with escalation of Sino-Taiwanese frictions.
The theoretical framework of this article relies on neoclassical-realist approach, according to which international determinants are not automatically reflected in foreign policy decisions. Although external stimuli delineate the limits of a rational behavior on the international scene, domestic factors may either accelerate or slow down implementation of diplomatic goals. 2 As such, neoclassical realism provides analytical instruments to better explain shifts in foreign policy of a state in relatively short terms. By contrast, neoliberalism and constructivism put emphasis either on economic interdependence or on identity in international relations, which tend to be shaped over longer periods of time. 3 By stressing importance of structural determinants, in turn, neorealism completely ignores the impact of domestic factors on foreign policy decisions. 4 Regarding cross-strait relations, Japan's national interest generally lay in preserving the status quo to stabilize the regional security system. Depending on the ideological leanings and international strategies employed by Japanese decision-makers as well as the state of Sino-Japanese relations, however, Tokyo reacted differently both to cross-strait rapprochement and cross-strait frictions.
While Japan's Taiwan policy has attracted a considerable interest from researchers, less attention has been paid to the evolution of Tokyo's stance on cross-strait relations. It has been emphasized that Taiwan has been important for Japan due to its proximity to crucial sea lanes. 5 Intensification of dialogue between Tokyo and Taipei in recent years, in turn, has been attributed either to economic and social globalization 6 or to a hedging strategy of the two governments vis-à-vis continental China. 7 According to Lam Peng-Er, in its approach towards cross-strait relations Japan tried to keep a balance between avoiding deterioration of contacts with Beijing and not letting Taipei overly provoke China. 8 Rather than treating Tokyo's stance on cross-strait relations as a static policy, this article interprets it as a dynamic process dependent both on domestic and external stimuli. It is composed of four sections. In line with neoclassical realism, the first section examines both the international determinants (independent variables) and the domestic factors (intervening variables) behind Tokyo's approach to 'One China' policy. In this light, the subsequent two sections describe Japan's reaction to cross-strait rapprochement under the Ma administration and cross-strait frictions under the Tsai cabinet, respectively.

International and domestic determinants of Japan's 'One China' Policy
Under American pressure, Tokyo established official diplomatic relations with Taipei in 1952. Following Sino-American rapprochement under the Nixon administration, in turn, Japan switched diplomatic recognition to Beijing in September 1972. In a Sino-Japanese Joint Communiqué, the Japanese government admitted that it "fully understands and respects" the stance of China "that Taiwan is an inalienable part of the territory of the People's Republic of China." 9 While, in line with the 'One China' policy, Tokyo maintained official diplomatic relationship with only one of the two Chinese governments, it consequently refrained from making any judgment on the legal status of Taiwan. 10 At the same time, Japan and the ROC continued economic, cultural, and societal exchanges, managed by the Interchange Association in Taipei, and the Association of East Asian Relations in Tokyo (renamed the Taipei Economic and Cultural Representative Office in Japan in 1991). 11 Tokyo's approach towards its 'One China' policy and cross-strait relations was reflected in Japan's Diplomatic Bluebooks, the annual report on Japan's foreign policy and international diplomacy that is published by the Ministry of Foreign Affairs each year. After the normalization of diplomatic contacts with the PRC, Tokyo avoided mentioning Taiwan in description of relations with other countries. Unofficial exchange with Taiwan was first mentioned in the Diplomatic Bluebook 1987, but only regarding data on trade and tourist exchanges. 12 It is symptomatic that in the 1990 edition, the expression 'diplomatic relations' was put in quotation marks when referring to their establishment between Taiwan and several minor states. 13 Such nomenclature was in line with strict adherence to 'One China' policy. The Diplomatic Bluebook of 1991 reconfirmed that "Japan firmly maintains the position taken in the Japan-China Joint Communique of 1972, which will not change in the future," while stressing that "Japan promotes its relations with Taiwan, within the basic framework of the Japan-China relationship." 14 At the end of the Cold War, the Japanese government was interested in developing friendly relations with China not only to promote bilateral trade exchange, but also to counterbalance the Soviet influence in the region. Nevertheless, pro-Beijing moods started changing after the brutal suppression of student protests at the Tiananmen Square in 1989 and collapse of the Union of Soviet Socialist Republics (USSR) in 1991. At the same time, pro-Taiwanese sentiments in Japan grew stronger due to democratization initiated by President Lee Teng-hui. Tokyo intensified exchange with Taipei at the beginning of the 21 st century. In 2001, Taiwanese diplomats in Japan received identity documents that barely differed from the documents of the officials from other countries. Gradually, Japanese ministries upgraded semi-official contacts with Taiwan to the level of vice-ministers. 15 While Tokyo's exchange with Taipei intensified, Sino-Japanese relations continued deteriorating in the 1990s. Tokyo was concerned with the growing Chinese military budget and with provocative acts of the People's Liberation Army Navy in the East China Sea, related to bilateral disputes on delimitation of exclusive economic zones and territorial sovereignty over the Senkaku/Diaoyu Islands. 16 Sino-Japanese territorial frictions culminated during diplomatic crises of September 2010 and September 2012. While the former crisis was caused by a collision between a Chinese trawler and a Japanese patrol vessel near the disputed archipelago, the latter crisis resulted from nationalization of the Senkaku/Diaoyu Islands by the Noda administration. 17 Whenever Sino-Japanese relations deteriorated, also history issues between both countries reemerged. Beijing repeatedly demanded apologies for the atrocities committed by the Imperial Army during the Second World War, criticized biased descriptions of history in Japanese textbooks, and opposed Japanese prime ministers' visits to the Yasukuni Shrine. 18 Due to a growing number of bilateral frictions and the sudden rise of Chinese economic and military power, Tokyo started perceiving the PRC as a major security threat. In 2012, Prime Minister Abe Shinzō announced the concept of 'Asia's Democratic Security Diamond' to build a regional coalition against China, composed of Japan, India, Australia, and the US. Warning that the South China Sea "seems to become 'Lake Beijing'," Abe stressed that the international community should "safeguard the maritime commons stretching from the Indian Ocean region to the western Pacific." 19 Abe belonged to a pro-Taiwanese group in the Liberal-Democratic Party (LDP). 20 In the 1990s, he visited Taipei many times as the head of the party's Youth Division. Moreover, when he was acting head of the LDP Foreign Policy Division in 1997, he challenged the official stance of the Japanese government and claimed that Taiwan fell within the scope of new US-Japan security guidelines. 21 Nine members of the Abe cabinet were members of the Creation 'Japan' (Sōsei "Nippon") in 2012, 22 and as many as 15 ministers belonged to the Japan Conference Parliamentary Discussion Group (Nippon Kaigi Kokkai Giin Kondankai) in 2014. 23 These two ultraconservative policy groups shared the anti-communist and pro-Taiwanese stance of the prime minister.
The strengthening of the influence of pro-Taiwanese politicians was accompanied by a gradual demise of the pro-Beijing group in the LDP. Traditionally, close relations with the PRC were maintained by the lawmakers originating from the factions led by Tanaka Kakuei and Ōhira Masayoshi who as prime minister and foreign minister, respectively, had achieved normalization of Sino-Japanese relations in 1972. Pro-Beijing politicians paid attention not to provoke China regarding the Taiwan problem. For instance, in 1994, Foreign Minister Kōno Yōhei promised his Chinese counterpart Qian Qichen he would not let ROC President Lee Teng-hui visit Japan. 24 Nevertheless, due to intensification of Sino-Japanese frictions in the 1990s, it was no longer beneficial for Japanese politicians to boast connections with Beijing to draw electoral support. As a result, by the time Abe returned as prime minister, most of senior pro-Beijing lawmakers had already retired or passed away without being replaced by younger-generation politicians interested in establishing connections with China. 25 While Prime Ministers Suga Yoshihide (2020-2021) and Kishida Fumio (2021-present) lacked the pro-Taiwanese background of their predecessor, they remained dependent on Abe's support as the leader of the largest faction in the LDP. 26 Another domestic factor that influenced Japan's stance on cross-strait relations were opinion polls. The Japanese public generally felt sympathy towards Taiwan, while having a negative image of China. According to an opinion poll conducted by the Taipei Economic and Cultural Representative Office in Japan in 2019, as many as 78.1% of respondents were sympathetic to Taiwan, and 55% considered the ROC as their favorite foreign country in Asia. Moreover, 63.1% were convinced that Taiwan was Japan's reliable partner. 27 By contrast, according to an opinion poll conducted by the Cabinet Office in 2019, only 22.7% of respondents felt sympathy towards continental China. 28 Both international and domestic determinants of Japan's stance on cross-strait relations shifted in the post-Cold War period. While Tokyo's relations with Beijing deteriorated due to territorial disputes and history issues, exchange with Taipei intensified as a result of Taiwan's democratization and diplomatic endeavors of the LDP pro-Taiwan faction. The evolving international and domestic factors influenced Tokyo's policy both regarding cross-strait rapprochement and cross-strait frictions.

Japan and cross-strait rapprochement
Within the framework of 'One China' policy, Japan adapted its strategy towards Taiwan depending on the state of cross-strait relations. Under the Ma Ying-jeou administration (2008-2016), Taipei intensified diplomatic contacts and economic exchange with Beijing. Such policy was welcomed by 'dovish' Japanese lawmakers, but it presented a challenge for those politicians who wanted to counterbalance China's rise through cooperation with Taiwan.
Japan welcomed resumption of high-level talks between Beijing and Taipei after the end of Cold War. In November 1992, representatives of the PRC's Association for Relations Across the Taiwan Strait and the ROC's Straits Exchange Foundation agreed in Hong Kong to continue 'One China' policy. In the Diplomatic Bluebook 1992, Tokyo noticed Beijing's efforts to intensify exchanges with Taipei in various fields as well as the fact that both China and Taiwan successfully participated in Asia-Pacific Economic Cooperation (APEC). 29 Taipei returned to policy of rapprochement with Beijing following Kuomintang (KMT) leader Ma Ying-jeou's victory in presidential election in 2008. However, Ma's Japan policy contrasted with the stance of his predecessors. Unlike continental Chinese, the Taiwanese people generally did not hold anti-Japanese sentiments. Older-generation Taiwanese politicians felt nostalgia to the period when the island was a Japanese colony (1895-1945), and Lee Teng-hui even sided with Japan on the dispute over the Senkaku/Diaoyu Islands. 30 By contrast, Ma had actively participated in anti-Japanese rallies when he was a student both in the US and in Taiwan in 1971. At that time, he tried to put pressure on the Nixon administration to grant the sovereignty over the Senkaku/Diaoyu Islands to the ROC before the return of the Ryukyu Islands to Japan. In 1972, in turn, Ma engaged in protests against switching of official recognition from Taipei to Beijing by the Tanaka administration. He even threw eggs at Japanese special emissary Shiina Etsusaburō and promoted boycott of Japanese products. 31  wrote his PhD dissertation at the Harvard University on the legal aspects of Sino-Japanese dispute over the seabed boundary delimitation. After starting political career, he periodically participated in rallies supporting the ROC's claim regarding the Senkaku/Diaoyu Islands and criticized Japan for the colonial rule over Taiwan. While Ma assuaged his anti-Japanese stance and visited Japan twice before presidential election to increase his popularity among the pro-Japanese inhabitants of Taiwan, he lacked the affinity towards Japan of the older-generation politicians. 32 President Ma abandoned the confrontational posture against Beijing of his predecessor and intensified diplomatic, economic, and cultural exchange with the PRC. After assuming office in May 2008, he returned to the 1992 consensus, according to which both Taipei and Beijing accepted 'One China' policy, while maintaining their own interpretations of this concept. Ma declared he would base his mainland policy on "three no's -no independence, no unification, and no use of force." 33 Under his tenure, negotiations between Beijing's Taiwan Affairs Office and Taipei's Mainland Affairs Council resulted in intensification of bilateral trade, investment, and people-to-people exchange. In 2010, the ROC and the PRC signed the Economic Cooperation Framework Agreement (ECFA), aimed at establishing a free-trade area between the two sides. Appreciating Ma's initiatives, the PRC agreed for Taiwan to join the World Health Assembly and the International Civil Aviation Organization as an observer. Cross-strait rapprochement eased Tokyo's concerns over a potential conflict in the region. Following Ma Ying-jeou's electoral victory in 2008, Diplomatic Bluebooks stopped even mentioning Taiwan. After formation of the Abe cabinet in December 2012, in turn, Taiwan started being referred to as "an important partner" that "has close economic ties and active people-to-people exchange with Japan." 36 On the other hand, taking into account President Ma's anti-Japanese background and his policy of rapprochement with the PRC, Japanese conservative politicians feared that his posture would undermine their efforts for counterbalancing the rising China. Such concerns were evident after Ma's visit to Tokyo as Taipei mayor in July 2006. At a meeting with members of the Japan-Taiwan Parliamentary League, Ma was criticized by former Japan Defense Agency Director-General Ishiba Shigeru for avoiding a clear answer regarding why KMT opposed the Chen administration's plan of purchasing Patriot surface-to-air missiles from the US. 37 Many commentators stressed that KMT was inciting anti-Japanese nationalism as an instrument of competition against President Chen Shui-bian. Moreover, Japanese Chief Cabinet Secretary Abe Shinzō felt annoyed with an article published in the China Times after Ma's visit, which disclosed that Abe had presumably stressed his firm opposition against Taiwan independence. 38 According to the Japanese sources, Abe did not even meet Ma face-to-face, and a short telephone conversation between them did not exceed the framework of a courteous call. 39 It seems that Tokyo tried to draw Taipei away from forming a potential common front against Japan with Beijing regarding territorial and history issues by displaying an accommodative posture towards the Ma administration. Ma's victory in the ROC presidential election almost coincided with a diplomatic crisis related to an incident in the East China Sea. On June 10, 2008, a Taiwanese angling boat sank due to a collision with a Japanese Coast Guard vessel near the Senkaku/Diaoyu Islands. Japanese cost guards released 13 anglers and detained three crew members for investigation. The incident met with a decisive protest from Taipei, which reconfirmed its claim over the disputed archipelago and demanded compensation and immediate release of the boat captain. On June 13, 2008, the ROC Prime Minister Liu Chao-shiuan even stated that Taipei did not exclude to use military force against Japan. When, on the following day, the boat captain was charged for having caused the collision, the Ma administration recalled its representative from Japan. On June 16, in turn, a trawler with Taiwanese activists, escorted by Taiwanese patrol vessels, entered waters near the Senkaku/Diaoyu Islands to manifest they were part of the ROC territory. Tokyo seemed surprised with the strength of the Ma administration's reaction. The Interchange Association in Taipei even issued a warning that Japanese nationals in Taiwan were endangered due to a sudden rise in anti-Japanese sentiments. Despite this fact, the Fukuda administration quickly decided to concede to Taiwanese demands. On June 20, 2008, the Japanese authorities not only released the boat captain, but also apologized to him and promised to pay compensation. 40 32 Ibidem, pp. 177-204. 33 41 However, after assuming power, pro-Taiwanese DPJ politicians intensified contacts with KMT as well. At the end of 2009, Interchange Association Director Saitō Masaki resigned, allegedly due to the fact that he had irritated President Ma by stating that the international status of Taiwan remained unresolved. 42 In 2010, the Interchange Association and the Association of East Asian Relations signed a memorandum, in which both sides expressed their will to develop cooperation for maintaining maritime security and order -the first document of this kind since 1972. 43 Also, the Great East Japan Earthquake of March 11, 2011, became an opportunity to enhance bilateral friendship due to the disaster relief aid amounting to 20 billion yen provided by Taipei. Such cooperation led to signature of investments and private flight arrangements between both sides. 44 An accommodating posture towards Taiwan was further strengthened by the LDP after its victorious parliamentary election in December 2012. In April 2013, only four months after Abe Shinzō once more became prime minister, Tokyo and Taipei concluded a fisheries agreement that ended difficult, 17-year long negotiations. 45 Japan conceded to many demands of the ROC. In particular, it allowed Taiwanese trawlers to enter disputed waters and increased the zone available to them by 1,400 square nautical miles. Such concession was probably aimed at preventing the Ma administration from forming a united front with Beijing over the territorial dispute with Japan. 46 Moreover, the fisheries agreement paved way towards a whole series of semi-governmental arrangements between the Interchange Association and the Taipei Economic and Cultural Representative Office in Japan.
Both international and domestic factors influenced Tokyo's response to cross-strait rapprochement. Immediately after the end of Cold War Japanese politicians did not treat China as a major security threat and the pro-Beijing faction in the LDP was still strong, so Tokyo welcomed the 1992 consensus between the PRC and the ROC. However, growing assertiveness of China on the international scene made Japanese statespersons perceive cross-strait rapprochement under the Ma administration as a potentially anti-Japanese initiative. As a result, both the DPJ and the LDP governments, which included many pro-Taiwanese politicians, instituted a range of measures aimed at drawing Taipei away from forming a united front with Beijing regarding territorial dispute and history issues.

Japan and cross-strait frictions
Cross-strait frictions reappeared whenever supporters of Taiwanese independence assumed power in the ROC. When the DPP came back to power under the Tsai Ing-wen administration in 2016, Taipei shifted to an assertive posture against Beijing. While such a situation enabled Japanese conservatives to use Taiwan in counterbalancing China, it also caused security concerns in the region.
Japan's official statements regarding cross-strait relations were a reaction to heightened tensions between Beijing and Taipei. China's nuclear tests in 1995 and military maneuvers in 1996 prompted Tokyo to express concerns about situation in the Taiwan Strait in their Diplomatic Bluebooks for the first time. In the 1996 edition, it was emphasized: "With regard to the Taiwan question, Japan has called on both parties to resolve their differences peacefully, to ensure peace and stability in East Asia." 47 To discourage Beijing from applying military pressure on Taipei, Tokyo temporarily suspended yen loans within the Official Development Assistance (ODA) to the PRC in 1996. In the same year, the Foreign Affairs Committee of the Japanese House of Councilors passed the first parliamentary resolution relating to Taiwan since 1972, in which it welcomed democratic presidential election in that country, expressed hope for further development of democracy and human rights both in Taiwan and China, recommended creation of measures to avoid acceleration of arms race in the region, and called for a peaceful resolution of the Taiwan problem. 48 Reportedly, Prime Minister Hashimoto Ryūtarō even secretly contacted President Lee Teng-hui and agreed to persuade the US to send a patrol fleet near Taiwan during the Strait crisis. 49 In the 1998 Diplomatic Bluebook, in turn, Tokyo stressed that "Japan has continued to express that it strongly desires to see a peaceful resolution of the Taiwan issue through peaceful talks between parties on both sides of the Strait, and is watching closely moves toward the resumption of dialogue." 50 While reassuring China about the unofficial character of contacts with Taipei, Tokyo continued encouraging both sides to start negotiations during cross-strait frictions under the Chen Shui-bian administration. For instance, in the Diplomatic Bluebook 2001, Tokyo emphasized that "Japan has maintained its relations with Taiwan as exchanges of a private and regional nature, or, in other words, working relations on a non-governmental basis," but it also expressed hope that "cross-Strait dialogue will be resumed at an early point." 51 What is important, in the 2005 edition Tokyo declared it considered situation in the Taiwan Strait as an issue "with a direct bearing on Japan's security." 52 In order to assuage regional frictions, the Japanese government periodically discouraged the DPP administration from provoking the PCR. In 2004, Tokyo expressed concerns over President Chen Shui-bian's plan to hold a referendum against China's military buildup, and Japanese Foreign Minister Kawaguchi Yuriko stated that Japan did neither support a "two Chinas" nor a "one China, one Taiwan" policy. 53 In the 2004 Diplomatic Bluebook, Tokyo even admitted that "as the movements such as the referendum increased pointlessly tensions in the China-Taiwan relationship, Japan appealed for Taiwan to handle the issues carefully and declared repeatedly to the Chinese side that a peaceful resolution to the Taiwan issue was important." 54 Moreover, in 2006, when Chen decided to suspend the guidelines for national unification, the Japanese Ministry of Foreign Affairs announced that Japan did not support any unilateral change in the status quo over the Strait. 55 On the other hand, in 2005, Japan expressed concerns regarding Chinese Anti-Secession Law -a document that did not exclude non-peaceful means to stop Taiwan's independence. 56 Tokyo stressed that "the Law might exert a negative influence over peace and stability in the Taiwan Straits and also relations between the two sides of the straits, which have been improving recently." 57 Frictions between Beijing and Taipei returned when another DPP leader, Tsai Ing-wen, won the presidential election in January 2016. The Sunflower Movement against the Cross-Strait Service Trade Agreement in spring 2014 showed the limits of rapprochement between Taipei and Beijing. 58 Tsai rejected the 1992 consensus while supporting maintenance of the status quo and not promoting declaration of Taiwan's independence. Such policy of "de facto one countries on each side" met with hostility from Beijing, which regarded acceptation of 'One China' policy as a precondition for diplomatic negotiations with Taipei. 59 The PRC intensified a campaign against Taiwan's membership in any international organizations even under the name 'Chinese Taipei' and put pressure on international airlines to add descriptions such as 'Province of China' to 'Taiwan'. In January 2017, Chinese aircraft carrier circumnavigated Taiwan for the first time. In January 2019, in turn, President Xi Jinping warned that China did "not forsake the use of force" as a means of reunification of Taiwan. 60 President Tsai's reelection in January 2020 pushed Beijing to further strengthen anti-Taiwanese rhetoric and increase the number of violations of Taiwan's sea and air zone. In particular, in the first week of October 2021, before the 110 th anniversary of the Xinhai Revolution, as many as 150 Chinese warplanes flew into Taiwan's air defense identification zone, which prompted Taiwanese Defense Minister Chiu Kuo-cheng to warn that a potential "misfire" could lead to a military conflict. 61 Exacerbation of cross-strait frictions was instrumental for those Japanese conservatives who supported an assertive policy towards the PRC. Tsai Ing-wen attached a much greater importance to Taiwan-Japanese relations than Ma Ying-jeou. While she lacked pro-Japanese nostalgia characteristic of the older-generation Taiwanese politicians, she did not have an anti-Japanese background either. Most importantly, Japan, along with the US, served for the DPP as a counterbalance against China. Before the presidential election, Tsai had probably met Prime Minister Abe during her visit to Japan in October 2015. As soon as her victory was announced, the Japanese foreign minister issued a warm message that stressed bilateral cooperation, and Prime Minister Abe congratulated her election in the House of Representatives. When Tsai assumed office, she reverted Ma's statement that Taipei regarded Japan-owned Okinotori Island in the Philippine Sea as a reef that did not allow Japan to extend its exclusive economic zone. 62 Cordial relations between both governments were symbolized by the fact that Tokyo did not take Taiwan, unlike South Korea, to the World Trade Organization appellate body regarding restrictions on Japanese seafood imports imposed after the 2011 Fukushima Daiichi Nuclear Power Plant disaster. 63 Gradually, Tokyo became more willing to elevate diplomatic contacts with Taipei, even at the risk of deteriorating relations with Beijing. In January 2017, the Interchange Association was renamed Japan-Taiwan Exchange Association, and in May 2017, the Taipei Economic and Cultural Representative Office in Japan changed its official name to the Association of Taiwan-Japan Relations. 64 At the same time, the number of mutual visits by high-ranking officials increased significantly. In March 2017, Senior Vice-Minister of Internal Affairs and Communications Akama Jirō, as the first Japanese representative of that level since 1972, attended a Japanese tourism fair in Taiwan. 65 Interestingly, Japan's Diplomatic Bluebooks increasingly stressed affinity with Taiwan, without discouraging Taipei from provoking Beijing nor even calling for a peaceful resolution of the Taiwan issue. In the Diplomatic Bluebook 2018, Taiwan was described as "a friend of Japan" for the first time. 66 In the 2019 edition, it was called "a crucial partner and an important friend, with which it shares fundamental values such as freedom, democracy, basic human rights, and the rule of law, and enjoys close economic relations and people-to-people exchanges." 67 In the Diplomatic Bluebook 2020, in turn, Taiwan's status was elevated to "an extremely crucial partner and an important friend," and Tokyo stressed it "has consistently supported the participation of Taiwan as an observer in the WHO General Assembly." 68 The 2021 edition further explained that "Japan has traditionally considered that there should be no geographical gap in responding to international health issues." 69 When the Coronavirus pandemic began at the beginning of 2020, Prime Minister Abe supported Taiwan's bid for an observer status in the World Health Organization (WHO), and he said it was "very regrettable" that Taipei was not allowed to take part in the WHO assembly in May 2020. 70 A growing number of Chinese provocative acts over the Taiwan Strait in 2021 prompted Tokyo to express support for Taipei more vocally. On April 16, 2021, Prime Minister Suga Yoshihide and President Joseph Biden stressed "the importance of peace and stability across the Taiwan Strait," encouraged "the peaceful resolution of cross-Strait issues", and expressed commitment "to peacefully resolving disputes and to opposing coercion." 71 It was the first mentioning of Taiwan in an official US-Japanese statement since normalization of diplomatic relations between Tokyo and Beijing in 1972. Similar statements appeared during the EU-Japan summit in May 72 and the Japan-Australia 2+2 Foreign and Defense Ministerial Consultations in June 2021, 73 which indicates that it was Tokyo that promoted global interest in the Taiwan problem.
Frictions in cross-strait relations influenced not only diplomatic initiatives, but also the security policy of Japan. In June 2021, Defense Minister Kishi Nobuo (Abe Shinzō's brother) expressed his concern about the fact that military asymmetry between China and Taiwan was widening every year. As he said: "The peace and stability of Taiwan are directly connected to Japan and we are closely monitoring ties between China and Taiwan, as well as Chinese military activity." 74 Preparing for a new Taiwan Strait crisis, Japanese and US military officials even reportedly started top-secret tabletop war games and joint exercises in the East China Sea and South China Sea. 75 Moreover, in August 2021, the LDP Taiwan Policy Project Team for the first time held official security talks with Taiwan on parliamentary level. 76 In addition, in 2021, Japan for the first time stated in defense white paper that "stabilizing the situation surrounding Taiwan is important for Japan's security and the stability of the international community." 77 The Russian invasion of Ukraine in February 2022 once more drew attention to the Taiwan problem. During his visit to London in May 2022, Prime Minister Kishida Fumio even stressed that "Ukraine might be East Asia tomorrow," thus implying the need to deter a potential Chinese attack on Taiwan. 78 In the 2022 edition of the defense white paper, Tokyo stressed: "The stability of the situation surrounding Taiwan is also critical for Japan's security and must be closely monitored with a sense of urgency while cooperating with the international community, based on the recognition that changes to the status quo by coercion are globally shared challenges." 79 Tokyo started even more explicitly condemning Beijing's pressure on Taipei following the launch of live-fire military exercises by the People's Liberation Army in the Taiwan Strait as a reaction to US House Speaker Nancy Pelosi's visit to Taiwan at the beginning of August 2022. On August 3, 2022, Foreign Minister Hayashi Yoshimasa signed the G7 Foreign Ministers' Statement on Preserving Peace and Stability Across the Taiwan Strait, which warned that "The PRC's escalatory response risks increasing tensions and destabilizing the region." 80 Moreover, when five Chinese missiles fell to the Japanese exclusive economic zone on the following day, Japanese Vice-Minister for Foreign Affairs Mori Takeo strongly protested to Chinese Ambassador to Japan Kong Xuanyou and requested "the immediate cessation of military training." 81  Minister Penny Wong during their meeting in Phnom Penh on August 5, 2022. 82 On the same day, Prime Minister Kishida Fumio met US House Speaker Nancy Pelosi, with whom he stressed that both sides would "work closely together to maintain peace and stability in the Taiwan Strait." 83 Both international and domestic factors were of importance in delineating Japan's stance regarding cross-strait frictions. While Tokyo warned the Chen administration against provoking Beijing, it not only showed a decisive support for the Tsai administration, but also promoted cooperation of like-minded countries over the Taiwan issue. This shift can be explained by an increased perception of China as a threat to regional security and the demise of the pro-Beijing faction in the LDP.

Conclusion
International determinants favored Japan's greater involvement in cross-strait relations after the end of Cold War. In line with the neorealist interpretation, Tokyo's approach towards the Taiwan problem generally evolved along with the balance of power in the region. The policy of containing the rising China in a natural way pushed Japan towards supporting Taiwan on the international scene. While in the early 1990s, Japan perceived cross-strait rapprochement as a way for stabilizing the regional security system, under the Ma administration, it tried to draw Taiwan away from forming a joint front with the PCR regarding territorial dispute and history issues. Whenever cross-strait relations deteriorated, in turn, Tokyo was concerned with regional security instability. While the Koizumi cabinet warned President Chen Shui-bian against provoking China, the Abe administration seemed more supportive of President Tsai Ing-wen's international initiatives. This change reflects the ROC's growing importance in Japan's strategy of counterbalancing China's rise. Strengthening of Japan's economic ties with Taiwan, stressed by neoliberalism, or mutual perception as friends between Tokyo and Taipei, emphasized by constructivism, were helpful in that process, but these factors alone cannot explain the differences between the succeeding Japanese governments' approach to cross-strait relations.
As predicted by neoclassical realism, domestic factors amplified Tokyo's response to external stimuli. The fact that pro-Taiwanese politicians, such as Prime Minister Abe Shinzō, assumed power in Japan, while the pro-Beijing faction in the LDP almost disappeared, accelerated intensification of ties with Taipei. The new generation of Japanese politicians stopped perceiving Tokyo's engagement in cross-strait relations as a taboo, which facilitated taking advantage of the Taiwan problem in foreign policy.
Still, the limits of a rational policy of containing China were delineated by international determinants. Faced with China's provocative acts in the Taiwan Strait, Japan continued promoting a peaceful solution of the Taiwan problem. For that reason, although Tokyo became more vocal in lobbying for Taipei on the international scene, it never crossed the red line of supporting Taiwan's independence.

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